Dry lime and sulfur product and method of making the same



- U TED STATES PATENT Gama;

os'cnn'rnnn 'nnnnunune; or rrr'rsnuncrn, PENNSYLVANIA, AssIeNon 'ro FRANK o.

. morons, or TOLEDO, OHIO.

No Drawing.

To all wltom it may concern:

Be it known that I, OSCAR F. HEDEN- BURG, residing at Pittsburgh, in the, countyot Allegheny, State of Pennsylvania, have 1nvented certain new and-useful Improvements in Dry Lime and" Sulfur Products and' Methods of Making the Same; and Iv do ,hereby declare the following to be a full,

clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains: to make and use the same. I I

My invention relates to lime and sulfur products, such for example as the compounds of lime andsulfur commonly employed as germlcides, insecticides and the like. The main objects of the invention are to provide a new and improved dry product of'lime and sulfur and method of making the same. Other objects of the invention will be brought out in the course of the following description.

It is well understood in the art that the productscommercially known as lime and sulfur are mainly chemical compounds of calcium and sulfur, principally'polysulfids of calcium, audit is "to the production of such products in dry form that the present invention particularly relates.

Solutions of lime and'sulfur for use particularly as germicides; insecticides and the likeFare wellknow'n. Such solutions are generally prepared by heating to boiling a mixture of water, water slaked lime .and

sulfur; one part of lime to 2, or 2.25, parts.

of sulfur being used, with sufiicient water to obtain a, solution of the desired specific gravity, 'or Baum. The reaction is' usually represented as follows:

According to this equation, there isv formed calcium. pentasulfid andcalcium thiosulfate. At the boiling temperature, however, calcium thiosulfate decomposes partially to give calcium sulfite and sulfur,

Accordingly, in practice, less sulfur is generally used than is represented by the first equation. The correct amount of sulmay LIME AINDISULFUR. r'nonucr AND Mart-ion or MAKING 'rnn'sann.

specificationofi Letters Patent. Patented Apr. 13, 1920. I 1 Application filed me ts 20, 1918. Serial No. 263,355.

The commercial solution oifered. for sale is about 33 Baum, or 1.2946 specific grav-' ity. This solution contains mainly calclum probably present in the solution, but the polysulfids are generally calculated as pentasulfid." It is upon the polysulfid content that the insecticidal value of the solution depends. More concentrated solutions, 384O Baum (13551-1381 specific gravity) can be made, but such solutions are liable to deposit crystals on standing whereby the solution itself becomes lower in grav ity, or Baum.

7 A dry lime and sulfur product is very desirable, because such dry product can be handled more easily than the solution. In order to obtain the dry lime and sulfur product, solutions thereof have heretofore beendistilled in cacao to remove substantially all of the water. Asheretofore practised, the distillation is carried on until a dry product remains in the still, and where the operation is carried out in a glass still, the still is broken to remove the product. The final product thus obtained is a dry powdered amorphous substance of light yellow color containing a relatively high per-- centage, usually about 15%, of insoluble matter, which settles very slowly during any subsequent attempt to dissolve the product. This relatively high percentage of insoluble matter in the dry product is, of course, objectionable.

I have discovered that when a lime and sulfur solution is greatly concentrated by distillation in a good Vacuum, say, forexample, about 29 inches of mercury, at a temperature of from about C. to about 80 C. a liquid product is obtained which can be readily'poured while hot, and which will harden on cooling so as to form a substantially physically dry lime and sulfur product. physically dry lime and sulfur product canthus be obtained by removing sufficient water from a lime and sulfur solution by distillation in vacuo and pouring the resulting concentrated liquid while hot into suitable. molds to harden upon cooling. I have found that the distillation should be carried on until not more than about 40% of water remains in the concentrated liquid, since the presence of a greater percentage of water will prevent hardening of the product uponcooling, and I have also found that at least about 20% of water should be left in the liquid in order to maintain sufficient fluidity for satisfactory pouring.

A product containing about 35% of water has been found to be the .mostsatisfactory,

since it contains the least amount of insoluble matter. I p that when the distillation 1s carried on until In this connection I have found less than about 35% of water is left inthe concentrated liquid, hydrogen sulfid 'is evolved rapidly and the loss of this sub stance seems toaccount for the increase 'in insoluble matter contained in the hardened product.

i When the distillation has been carried on until the concentrated" liquid contains about 35% of water, I have found that the dry and hardened product obtained by cooling contains generally less than about 5% of insoluble matter, whereas if the distillation is carand easily hardens upon cooling and contains a relatively small amount of insoluble matter.

In carrying out the method of the invention, I concentrate a suitable solution of lime and sulfur, obtained, for example, as described in the fore part of this specification, by evaporation or distillation in a good vacuum at a temperature of between C.

and 80 C. As previously-stated, I have i found a'vacuum of about 29 inches of mercury to be suitable for carrying out the process. he concentration of the solution is continued until the desired amount of water has been removed and the concentrated liquidis then poured while hot intosuitable molds, and will upon cooling become hardand crystalline in structure. The hardened product is sufficiently dry for all commercial purposes and may be broken up or reduced tosuch form as'is most convenient for use.

While I prefer to carry on the evaporation or distillation until a concentrated .so-

lution of lime and sulfur containing about 35% of water is obtained, it will, of course, be understood that I do not wish to be liniited to'this particular percentage of watercontent; and in general the 'concentrationis carried on until sufficient water is'removed from the solution so that. the resultinglmass will solidifyor crystallize upon cooling, and so that the amount of mechanically held water is not sufficient to drain away 'from the solid mass in any substantial amount.

' have found that the lime and sulfur solution \proved dry product of the present invention may be solidified or hardened in a granular form. The general procedure is the same up to the point of pouring the concentrated liquid. Where a granular product is desired, the liquidmass is stirred while cool ing, thus producing a granulated lime and sulfur product which is a mixture of crysv. tals and contains about the same percentage of insoluble matter as the molded product.

I claim: 1. The method of producing a dry lime and sulfurproduct which consists in distilling a solution of lime and sulfur until the resulting concentrated product will pour while hot and harden upon cooling, and solidifying such resulting concentrated prod-.

- uct by cooling the same.

2. The method of producing a dry. lime and sulfur product which consists in concentrating a solution of lime and sulfur until the percentage of water remaining therein is between 20 and 4:0, and solidifying the resulting concentrated liquid by cooling the same.

3. The method of producing a dry lime and sulfur product, which consists in distilling a solutionofl lime and sulfur in a vacuum of about 29 inches of mercury, and

thereby reducing the water content thereof tobetween 20 and 40%, and hardening the resulting concentrated solution by cooling the same. f

4. The method of producing a dry lime and sulfur product, which consists in con-'lzo centrating a solution of lime and sulfur until the water content thereof is about 35%, and hardening the resulting concentrated solution by cooling the same.

5. The method of producing a dry lime and sulfur product, which consists in distilling a solution of lime and sulfur in a good vacuum and at a temperature ranging from about 55 -C. to about 80 C., and

therebyreducing the water content of the solution to between 20 and 40%, and hardening the resulting" concentrated solution by cooling the same.

- ing'from about 559 C./'to about 80C., and

thereby I removing from the solution a sufficient amount of waterso that the resulting concentrated solution will pour while hot and harden upon cooling, and hardening such resulting concentrated solution by coolthe sam 1 :-'A new article of manufacture comprising'a dry lime and sulfur prgduct composed 40%of water.

principally of a, polysul fid polysulfids of calcium and containing between 20% and 8; A-new'articleof m'anugfacture comprising a dry lime and sulfurproduct composed principally of a polysulfid orpolysulfids of calcium and containmg about 35% of water.

9. A new article of manufacture comprising a dry lime and sulfur (product composed principally of a polysulfi calcium and containing less than about 12% of insoluble matter.

10. A new article of manufacture comprising a dry lime and sulfur product containing about 35% of water, and less than about of insoluble matter.

11. A new article of manufacture comprising a dry crystalline composition of lime and sulfur containing between and 40% of water. v v v 12. A new article of manufacture comprising' a dry crystallinepolysulfid or polysulfids of calcium-containingbetween 20% and 40% of water.

13. A new article of manufacture comprising a dry crystalline polysulfid or polysulfids of calcium containing about 35% of water and less than about" 5% ofinsoluble matter. I

In testimony whereof I afiix my signature.

OSCAR FRED HEn NBUnG. 

